The rapid development of the field of teratology is a reflection of the increasing concern of the scientific community concerning the influence of environmental contaminants on the development of the fetus and the newborn child. Whereas several chemicals are known to produce structural abnormalities following perinatal exposure it is becoming apparent that the subtle toxic effects that may occur in the absence of any observable growth abnormalities might present a greater hazard to man than the more apparent structural changes. It is, therefore, incumbent upon us to develop more sensitive tests to evaluate biochemical and physiological deficits in organ function so as to predict possible hazards to man. This proposal is designed to evaluate, systematically and quantitatively, the effect of perinatal exposure to environmental chemicals on subsequent renal function in newborn and adult animals. We will develop the methods necessary to assess abnormalities of renal function in newborn and developing animals. These studies will include assessment of direct changes in renal function and indirect changes that will be seen following stresses such as water deprivation, electrolyte excess or deficit, diet, drugs, toxicants, etc. Also included will be evaluation of the temporal course of these effects including time of onset, presistance into adulthood, etc. Lastly, we will determine, where possible, the biochemical mechanisms whereby the above changes are produced with the goal to obtain predictive information concerning the potential hazard of these and similar agents to man. We will evaluate quantitatively a variety of enzyme systems associated with the activation and deactivation of toxicants by the kidney. It is our contention that several of the more common pesticides will alter several of these enzyme activities within the kidney during development and in this way act a modifiers of the action of the other toxic agents.